git.sur5r.net Git - openldap/blob - servers/slapd/backover.c

   1 /* backover.c - backend overlay routines */
   2 /* $OpenLDAP$ */
   3 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   4  *
   5  * Copyright 2003-2017 The OpenLDAP Foundation.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted only as authorized by the OpenLDAP
  10  * Public License.
  11  *
  12  * A copy of this license is available in the file LICENSE in the
  13  * top-level directory of the distribution or, alternatively, at
  14  * <http://www.OpenLDAP.org/license.html>.
  15  */
  16
  17 /* Functions to overlay other modules over a backend. */
  18
  19 #include "portable.h"
  20
  21 #include <stdio.h>
  22
  23 #include <ac/string.h>
  24 #include <ac/socket.h>
  25
  26 #define SLAPD_TOOLS
  27 #include "slap.h"
  28 #include "config.h"
  29
  30 static slap_overinst *overlays;
  31
  32 static int
  33 over_db_config(
  34         BackendDB *be,
  35         const char *fname,
  36         int lineno,
  37         int argc,
  38         char **argv
  39 )
  40 {
  41         slap_overinfo *oi = be->bd_info->bi_private;
  42         slap_overinst *on = oi->oi_list;
  43         BackendInfo *bi_orig = be->bd_info;
  44         struct ConfigOCs *be_cf_ocs = be->be_cf_ocs;
  45         ConfigArgs ca = {0};
  46         int rc = 0;
  47
  48         if ( oi->oi_orig->bi_db_config ) {
  49                 be->bd_info = oi->oi_orig;
  50                 be->be_cf_ocs = oi->oi_orig->bi_cf_ocs;
  51                 rc = oi->oi_orig->bi_db_config( be, fname, lineno,
  52                         argc, argv );
  53
  54                 if ( be->bd_info != oi->oi_orig ) {
  55                         slap_overinfo   *oi2;
  56                         slap_overinst   *on2, **onp;
  57                         BackendDB       be2 = *be;
  58                         int             i;
  59
  60                         /* a database added an overlay;
  61                          * work it around... */
  62                         assert( overlay_is_over( be ) );
  63
  64                         oi2 = ( slap_overinfo * )be->bd_info->bi_private;
  65                         on2 = oi2->oi_list;
  66
  67                         /* need to put a uniqueness check here as well;
  68                          * note that in principle there could be more than
  69                          * one overlay as a result of multiple calls to
  70                          * overlay_config() */
  71                         be2.bd_info = (BackendInfo *)oi;
  72
  73                         for ( i = 0, onp = &on2; *onp; i++, onp = &(*onp)->on_next ) {
  74                                 if ( overlay_is_inst( &be2, (*onp)->on_bi.bi_type ) ) {
  75                                         Debug( LDAP_DEBUG_ANY, "over_db_config(): "
  76                                                         "warning, freshly added "
  77                                                         "overlay #%d \"%s\" is already in list\n",
  78                                                         i, (*onp)->on_bi.bi_type, 0 );
  79
  80                                         /* NOTE: if the overlay already exists,
  81                                          * there is no way to merge the results
  82                                          * of the configuration that may have
  83                                          * occurred during bi_db_config(); we
  84                                          * just issue a warning, and the
  85                                          * administrator should deal with this */
  86                                 }
  87                         }
  88                         *onp = oi->oi_list;
  89
  90                         oi->oi_list = on2;
  91
  92                         ch_free( be->bd_info );
  93                 }
  94
  95                 be->bd_info = (BackendInfo *)oi;
  96                 if ( rc != SLAP_CONF_UNKNOWN ) return rc;
  97         }
  98
  99         ca.argv = argv;
 100         ca.argc = argc;
 101         ca.fname = fname;
 102         ca.lineno = lineno;
 103         ca.be = be;
 104         snprintf( ca.log, sizeof( ca.log ), "%s: line %d",
 105                         ca.fname, ca.lineno );
 106         ca.op = SLAP_CONFIG_ADD;
 107         ca.valx = -1;
 108
 109         for (; on; on=on->on_next) {
 110                 rc = SLAP_CONF_UNKNOWN;
 111                 if (on->on_bi.bi_cf_ocs) {
 112                         ConfigTable *ct;
 113                         ca.bi = &on->on_bi;
 114                         ct = config_find_keyword( on->on_bi.bi_cf_ocs->co_table, &ca );
 115                         if ( ct ) {
 116                                 ca.table = on->on_bi.bi_cf_ocs->co_type;
 117                                 rc = config_add_vals( ct, &ca );
 118                                 if ( rc != SLAP_CONF_UNKNOWN )
 119                                         break;
 120                         }
 121                 }
 122                 if (on->on_bi.bi_db_config && rc == SLAP_CONF_UNKNOWN) {
 123                         be->bd_info = &on->on_bi;
 124                         rc = on->on_bi.bi_db_config( be, fname, lineno,
 125                                 argc, argv );
 126                         if ( rc != SLAP_CONF_UNKNOWN ) break;
 127                 }
 128         }
 129         be->bd_info = bi_orig;
 130         be->be_cf_ocs = be_cf_ocs;
 131
 132         return rc;
 133 }
 134
 135 static int
 136 over_db_open(
 137         BackendDB *be,
 138         ConfigReply *cr
 139 )
 140 {
 141         slap_overinfo *oi = be->bd_info->bi_private;
 142         slap_overinst *on = oi->oi_list;
 143         BackendDB db = *be;
 144         int rc = 0;
 145
 146         db.be_flags |= SLAP_DBFLAG_OVERLAY;
 147         db.bd_info = oi->oi_orig;
 148         if ( db.bd_info->bi_db_open ) {
 149                 rc = db.bd_info->bi_db_open( &db, cr );
 150         }
 151
 152         for (; on && rc == 0; on=on->on_next) {
 153                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 154                         continue;
 155                 db.bd_info = &on->on_bi;
 156                 if ( db.bd_info->bi_db_open ) {
 157                         rc = db.bd_info->bi_db_open( &db, cr );
 158                 }
 159         }
 160
 161         return rc;
 162 }
 163
 164 static int
 165 over_db_close(
 166         BackendDB *be,
 167         ConfigReply *cr
 168 )
 169 {
 170         slap_overinfo *oi = be->bd_info->bi_private;
 171         slap_overinst *on = oi->oi_list;
 172         BackendInfo *bi_orig = be->bd_info;
 173         int rc = 0;
 174
 175         for (; on && rc == 0; on=on->on_next) {
 176                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 177                         continue;
 178                 be->bd_info = &on->on_bi;
 179                 if ( be->bd_info->bi_db_close ) {
 180                         rc = be->bd_info->bi_db_close( be, cr );
 181                 }
 182         }
 183
 184         if ( oi->oi_orig->bi_db_close ) {
 185                 be->bd_info = oi->oi_orig;
 186                 rc = be->bd_info->bi_db_close( be, cr );
 187         }
 188
 189         be->bd_info = bi_orig;
 190         return rc;
 191 }
 192
 193 static int
 194 over_db_destroy(
 195         BackendDB *be,
 196         ConfigReply *cr
 197 )
 198 {
 199         slap_overinfo *oi = be->bd_info->bi_private;
 200         slap_overinst *on = oi->oi_list, *next;
 201         BackendInfo *bi_orig = be->bd_info;
 202         int rc = 0;
 203
 204         be->bd_info = oi->oi_orig;
 205         if ( be->bd_info->bi_db_destroy ) {
 206                 rc = be->bd_info->bi_db_destroy( be, cr );
 207         }
 208
 209         for (; on && rc == 0; on=on->on_next) {
 210                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 211                         continue;
 212                 be->bd_info = &on->on_bi;
 213                 if ( be->bd_info->bi_db_destroy ) {
 214                         rc = be->bd_info->bi_db_destroy( be, cr );
 215                 }
 216         }
 217
 218         on = oi->oi_list;
 219         if ( on ) {
 220                 for (next = on->on_next; on; on=next) {
 221                         next = on->on_next;
 222                         free( on );
 223                 }
 224         }
 225         be->bd_info = bi_orig;
 226         free( oi );
 227         return rc;
 228 }
 229
 230 static int
 231 over_back_response ( Operation *op, SlapReply *rs )
 232 {
 233         slap_overinfo *oi = op->o_callback->sc_private;
 234         slap_overinst *on = oi->oi_list;
 235         int rc = SLAP_CB_CONTINUE;
 236         BackendDB *be = op->o_bd, db = *op->o_bd;
 237
 238         db.be_flags |= SLAP_DBFLAG_OVERLAY;
 239         op->o_bd = &db;
 240         for (; on; on=on->on_next ) {
 241                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 242                         continue;
 243                 if ( on->on_response ) {
 244                         db.bd_info = (BackendInfo *)on;
 245                         rc = on->on_response( op, rs );
 246                         if ( rc != SLAP_CB_CONTINUE ) break;
 247                 }
 248         }
 249         /* Bypass the remaining on_response layers, but allow
 250          * normal execution to continue.
 251          */
 252         if ( rc == SLAP_CB_BYPASS )
 253                 rc = SLAP_CB_CONTINUE;
 254         op->o_bd = be;
 255         return rc;
 256 }
 257
 258 static int
 259 over_access_allowed(
 260         Operation               *op,
 261         Entry                   *e,
 262         AttributeDescription    *desc,
 263         struct berval           *val,
 264         slap_access_t           access,
 265         AccessControlState      *state,
 266         slap_mask_t             *maskp )
 267 {
 268         slap_overinfo *oi;
 269         slap_overinst *on;
 270         BackendInfo *bi;
 271         BackendDB *be = op->o_bd, db;
 272         int rc = SLAP_CB_CONTINUE;
 273
 274         /* FIXME: used to happen for instance during abandon
 275          * when global overlays are used... */
 276         assert( op->o_bd != NULL );
 277
 278         bi = op->o_bd->bd_info;
 279         /* Were we invoked on the frontend? */
 280         if ( !bi->bi_access_allowed ) {
 281                 oi = frontendDB->bd_info->bi_private;
 282         } else {
 283                 oi = op->o_bd->bd_info->bi_private;
 284         }
 285         on = oi->oi_list;
 286
 287         for ( ; on; on = on->on_next ) {
 288                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 289                         continue;
 290                 if ( on->on_bi.bi_access_allowed ) {
 291                         /* NOTE: do not copy the structure until required */
 292                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 293                                 db = *op->o_bd;
 294                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 295                                 op->o_bd = &db;
 296                         }
 297
 298                         op->o_bd->bd_info = (BackendInfo *)on;
 299                         rc = on->on_bi.bi_access_allowed( op, e,
 300                                 desc, val, access, state, maskp );
 301                         if ( rc != SLAP_CB_CONTINUE ) break;
 302                 }
 303         }
 304
 305         if ( rc == SLAP_CB_CONTINUE ) {
 306                 BI_access_allowed       *bi_access_allowed;
 307
 308                 /* if the database structure was changed, o_bd points to a
 309                  * copy of the structure; put the original bd_info in place */
 310                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 311                         op->o_bd->bd_info = oi->oi_orig;
 312                 }
 313
 314                 if ( oi->oi_orig->bi_access_allowed ) {
 315                         bi_access_allowed = oi->oi_orig->bi_access_allowed;
 316                 } else {
 317                         bi_access_allowed = slap_access_allowed;
 318                 }
 319
 320                 rc = bi_access_allowed( op, e,
 321                         desc, val, access, state, maskp );
 322         }
 323         /* should not fall thru this far without anything happening... */
 324         if ( rc == SLAP_CB_CONTINUE ) {
 325                 /* access not allowed */
 326                 rc = 0;
 327         }
 328
 329         op->o_bd = be;
 330         op->o_bd->bd_info = bi;
 331
 332         return rc;
 333 }
 334
 335 int
 336 overlay_entry_get_ov(
 337         Operation               *op,
 338         struct berval   *dn,
 339         ObjectClass             *oc,
 340         AttributeDescription    *ad,
 341         int     rw,
 342         Entry   **e,
 343         slap_overinst *on )
 344 {
 345         slap_overinfo *oi = on->on_info;
 346         BackendDB *be = op->o_bd, db;
 347         BackendInfo *bi = op->o_bd->bd_info;
 348         int rc = SLAP_CB_CONTINUE;
 349
 350         for ( ; on; on = on->on_next ) {
 351                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 352                         continue;
 353                 if ( on->on_bi.bi_entry_get_rw ) {
 354                         /* NOTE: do not copy the structure until required */
 355                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 356                                 db = *op->o_bd;
 357                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 358                                 op->o_bd = &db;
 359                         }
 360
 361                         op->o_bd->bd_info = (BackendInfo *)on;
 362                         rc = on->on_bi.bi_entry_get_rw( op, dn,
 363                                 oc, ad, rw, e );
 364                         if ( rc != SLAP_CB_CONTINUE ) break;
 365                 }
 366         }
 367
 368         if ( rc == SLAP_CB_CONTINUE ) {
 369                 /* if the database structure was changed, o_bd points to a
 370                  * copy of the structure; put the original bd_info in place */
 371                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 372                         op->o_bd->bd_info = oi->oi_orig;
 373                 }
 374
 375                 if ( oi->oi_orig->bi_entry_get_rw ) {
 376                         rc = oi->oi_orig->bi_entry_get_rw( op, dn,
 377                                 oc, ad, rw, e );
 378                 }
 379         }
 380         /* should not fall thru this far without anything happening... */
 381         if ( rc == SLAP_CB_CONTINUE ) {
 382                 rc = LDAP_UNWILLING_TO_PERFORM;
 383         }
 384
 385         op->o_bd = be;
 386         op->o_bd->bd_info = bi;
 387
 388         return rc;
 389 }
 390
 391 static int
 392 over_entry_get_rw(
 393         Operation               *op,
 394         struct berval   *dn,
 395         ObjectClass             *oc,
 396         AttributeDescription    *ad,
 397         int     rw,
 398         Entry   **e )
 399 {
 400         slap_overinfo *oi;
 401         slap_overinst *on;
 402
 403         assert( op->o_bd != NULL );
 404
 405         oi = op->o_bd->bd_info->bi_private;
 406         on = oi->oi_list;
 407
 408         return overlay_entry_get_ov( op, dn, oc, ad, rw, e, on );
 409 }
 410
 411 int
 412 overlay_entry_release_ov(
 413         Operation       *op,
 414         Entry   *e,
 415         int rw,
 416         slap_overinst *on )
 417 {
 418         slap_overinfo *oi = on->on_info;
 419         BackendDB *be = op->o_bd, db;
 420         BackendInfo *bi = op->o_bd->bd_info;
 421         int rc = SLAP_CB_CONTINUE;
 422
 423         for ( ; on; on = on->on_next ) {
 424                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 425                         continue;
 426                 if ( on->on_bi.bi_entry_release_rw ) {
 427                         /* NOTE: do not copy the structure until required */
 428                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 429                                 db = *op->o_bd;
 430                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 431                                 op->o_bd = &db;
 432                         }
 433
 434                         op->o_bd->bd_info = (BackendInfo *)on;
 435                         rc = on->on_bi.bi_entry_release_rw( op, e, rw );
 436                         if ( rc != SLAP_CB_CONTINUE ) break;
 437                 }
 438         }
 439
 440         if ( rc == SLAP_CB_CONTINUE ) {
 441                 /* if the database structure was changed, o_bd points to a
 442                  * copy of the structure; put the original bd_info in place */
 443                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 444                         op->o_bd->bd_info = oi->oi_orig;
 445                 }
 446
 447                 if ( oi->oi_orig->bi_entry_release_rw ) {
 448                         rc = oi->oi_orig->bi_entry_release_rw( op, e, rw );
 449                 }
 450         }
 451         /* should not fall thru this far without anything happening... */
 452         if ( rc == SLAP_CB_CONTINUE ) {
 453                 entry_free( e );
 454                 rc = 0;
 455         }
 456
 457         op->o_bd = be;
 458         op->o_bd->bd_info = bi;
 459
 460         return rc;
 461 }
 462
 463 static int
 464 over_entry_release_rw(
 465         Operation       *op,
 466         Entry   *e,
 467         int rw )
 468 {
 469         slap_overinfo *oi;
 470         slap_overinst *on;
 471
 472         assert( op->o_bd != NULL );
 473
 474         oi = op->o_bd->bd_info->bi_private;
 475         on = oi->oi_list;
 476
 477         return overlay_entry_release_ov( op, e, rw, on );
 478 }
 479
 480 static int
 481 over_acl_group(
 482         Operation               *op,
 483         Entry                   *e,
 484         struct berval           *gr_ndn,
 485         struct berval           *op_ndn,
 486         ObjectClass             *group_oc,
 487         AttributeDescription    *group_at )
 488 {
 489         slap_overinfo *oi;
 490         slap_overinst *on;
 491         BackendInfo *bi;
 492         BackendDB *be = op->o_bd, db;
 493         int rc = SLAP_CB_CONTINUE;
 494
 495         /* FIXME: used to happen for instance during abandon
 496          * when global overlays are used... */
 497         assert( be != NULL );
 498
 499         bi = be->bd_info;
 500         oi = bi->bi_private;
 501         on = oi->oi_list;
 502
 503         for ( ; on; on = on->on_next ) {
 504                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 505                         continue;
 506                 if ( on->on_bi.bi_acl_group ) {
 507                         /* NOTE: do not copy the structure until required */
 508                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 509                                 db = *op->o_bd;
 510                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 511                                 op->o_bd = &db;
 512                         }
 513
 514                         op->o_bd->bd_info = (BackendInfo *)on;
 515                         rc = on->on_bi.bi_acl_group( op, e,
 516                                 gr_ndn, op_ndn, group_oc, group_at );
 517                         if ( rc != SLAP_CB_CONTINUE ) break;
 518                 }
 519         }
 520
 521         if ( rc == SLAP_CB_CONTINUE ) {
 522                 BI_acl_group            *bi_acl_group;
 523
 524                 /* if the database structure was changed, o_bd points to a
 525                  * copy of the structure; put the original bd_info in place */
 526                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 527                         op->o_bd->bd_info = oi->oi_orig;
 528                 }
 529
 530                 if ( oi->oi_orig->bi_acl_group ) {
 531                         bi_acl_group = oi->oi_orig->bi_acl_group;
 532                 } else {
 533                         bi_acl_group = backend_group;
 534                 }
 535
 536                 rc = bi_acl_group( op, e,
 537                         gr_ndn, op_ndn, group_oc, group_at );
 538         }
 539         /* should not fall thru this far without anything happening... */
 540         if ( rc == SLAP_CB_CONTINUE ) {
 541                 /* access not allowed */
 542                 rc = 0;
 543         }
 544
 545         op->o_bd = be;
 546         op->o_bd->bd_info = bi;
 547
 548         return rc;
 549 }
 550
 551 static int
 552 over_acl_attribute(
 553         Operation               *op,
 554         Entry                   *target,
 555         struct berval           *entry_ndn,
 556         AttributeDescription    *entry_at,
 557         BerVarray               *vals,
 558         slap_access_t           access )
 559 {
 560         slap_overinfo *oi;
 561         slap_overinst *on;
 562         BackendInfo *bi;
 563         BackendDB *be = op->o_bd, db;
 564         int rc = SLAP_CB_CONTINUE;
 565
 566         /* FIXME: used to happen for instance during abandon
 567          * when global overlays are used... */
 568         assert( be != NULL );
 569
 570         bi = be->bd_info;
 571         oi = bi->bi_private;
 572         on = oi->oi_list;
 573
 574         for ( ; on; on = on->on_next ) {
 575                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 576                         continue;
 577                 if ( on->on_bi.bi_acl_attribute ) {
 578                         /* NOTE: do not copy the structure until required */
 579                         if ( !SLAP_ISOVERLAY( op->o_bd ) ) {
 580                                 db = *op->o_bd;
 581                                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 582                                 op->o_bd = &db;
 583                         }
 584
 585                         op->o_bd->bd_info = (BackendInfo *)on;
 586                         rc = on->on_bi.bi_acl_attribute( op, target,
 587                                 entry_ndn, entry_at, vals, access );
 588                         if ( rc != SLAP_CB_CONTINUE ) break;
 589                 }
 590         }
 591
 592         if ( rc == SLAP_CB_CONTINUE ) {
 593                 BI_acl_attribute                *bi_acl_attribute;
 594
 595                 /* if the database structure was changed, o_bd points to a
 596                  * copy of the structure; put the original bd_info in place */
 597                 if ( SLAP_ISOVERLAY( op->o_bd ) ) {
 598                         op->o_bd->bd_info = oi->oi_orig;
 599                 }
 600
 601                 if ( oi->oi_orig->bi_acl_attribute ) {
 602                         bi_acl_attribute = oi->oi_orig->bi_acl_attribute;
 603                 } else {
 604                         bi_acl_attribute = backend_attribute;
 605                 }
 606
 607                 rc = bi_acl_attribute( op, target,
 608                         entry_ndn, entry_at, vals, access );
 609         }
 610         /* should not fall thru this far without anything happening... */
 611         if ( rc == SLAP_CB_CONTINUE ) {
 612                 /* access not allowed */
 613                 rc = 0;
 614         }
 615
 616         op->o_bd = be;
 617         op->o_bd->bd_info = bi;
 618
 619         return rc;
 620 }
 621
 622 int
 623 overlay_callback_after_backover( Operation *op, slap_callback *sc, int append )
 624 {
 625         slap_callback **scp;
 626
 627         for ( scp = &op->o_callback; *scp != NULL; scp = &(*scp)->sc_next ) {
 628                 if ( (*scp)->sc_response == over_back_response ) {
 629                         sc->sc_next = (*scp)->sc_next;
 630                         (*scp)->sc_next = sc;
 631                         return 0;
 632                 }
 633         }
 634
 635         if ( append ) {
 636                 *scp = sc;
 637                 return 0;
 638         }
 639
 640         return 1;
 641 }
 642
 643 /*
 644  * default return code in case of missing backend function
 645  * and overlay stack returning SLAP_CB_CONTINUE
 646  */
 647 static int op_rc[ op_last ] = {
 648         LDAP_UNWILLING_TO_PERFORM,      /* bind */
 649         LDAP_UNWILLING_TO_PERFORM,      /* unbind */
 650         LDAP_UNWILLING_TO_PERFORM,      /* search */
 651         SLAP_CB_CONTINUE,               /* compare; pass to frontend */
 652         LDAP_UNWILLING_TO_PERFORM,      /* modify */
 653         LDAP_UNWILLING_TO_PERFORM,      /* modrdn */
 654         LDAP_UNWILLING_TO_PERFORM,      /* add */
 655         LDAP_UNWILLING_TO_PERFORM,      /* delete */
 656         LDAP_UNWILLING_TO_PERFORM,      /* abandon */
 657         LDAP_UNWILLING_TO_PERFORM,      /* cancel */
 658         LDAP_UNWILLING_TO_PERFORM,      /* extended */
 659         LDAP_SUCCESS,                   /* aux_operational */
 660         LDAP_SUCCESS,                   /* aux_chk_referrals */
 661         SLAP_CB_CONTINUE                /* aux_chk_controls; pass to frontend */
 662 };
 663
 664 int overlay_op_walk(
 665         Operation *op,
 666         SlapReply *rs,
 667         slap_operation_t which,
 668         slap_overinfo *oi,
 669         slap_overinst *on
 670 )
 671 {
 672         BackendInfo *bi;
 673         int rc = SLAP_CB_CONTINUE;
 674
 675         for (; on; on=on->on_next ) {
 676                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 677                         continue;
 678                 bi = &on->on_bi;
 679                 if ( (&bi->bi_op_bind)[ which ] ) {
 680                         op->o_bd->bd_info = (BackendInfo *)on;
 681                         rc = (&bi->bi_op_bind)[ which ]( op, rs );
 682                         if ( rc != SLAP_CB_CONTINUE ) break;
 683                 }
 684         }
 685         if ( rc == SLAP_CB_BYPASS )
 686                 rc = SLAP_CB_CONTINUE;
 687         /* if an overlay halted processing, make sure
 688          * any previously set cleanup handlers are run
 689          */
 690         if ( rc != SLAP_CB_CONTINUE )
 691                 goto cleanup;
 692
 693         bi = oi->oi_orig;
 694         if ( (&bi->bi_op_bind)[ which ] ) {
 695                 op->o_bd->bd_info = bi;
 696                 rc = (&bi->bi_op_bind)[ which ]( op, rs );
 697         }
 698         /* should not fall thru this far without anything happening... */
 699         if ( rc == SLAP_CB_CONTINUE ) {
 700                 rc = op_rc[ which ];
 701         }
 702
 703         /* The underlying backend didn't handle the request, make sure
 704          * overlay cleanup is processed.
 705          */
 706         if ( rc == LDAP_UNWILLING_TO_PERFORM ) {
 707                 slap_callback *sc_next;
 708 cleanup:
 709                 for ( ; op->o_callback && op->o_callback->sc_response !=
 710                         over_back_response; op->o_callback = sc_next ) {
 711                         sc_next = op->o_callback->sc_next;
 712                         if ( op->o_callback->sc_cleanup ) {
 713                                 op->o_callback->sc_cleanup( op, rs );
 714                         }
 715                 }
 716         }
 717         return rc;
 718 }
 719
 720 static int
 721 over_op_func_cleanup( Operation *op, SlapReply *rs )
 722 {
 723         slap_callback *cb = op->o_callback;
 724         if ( rs->sr_type == REP_RESULT && cb != NULL) {
 725                 op->o_callback = cb->sc_next;
 726                 ch_free( cb );
 727         }
 728 }
 729
 730 static int
 731 over_op_func(
 732         Operation *op,
 733         SlapReply *rs,
 734         slap_operation_t which
 735 )
 736 {
 737         slap_overinfo *oi;
 738         slap_overinst *on;
 739         BackendDB *be = op->o_bd, db;
 740         slap_callback **sc;
 741         slap_callback *cb = (slap_callback *) ch_malloc( sizeof( slap_callback ));
 742         int rc = SLAP_CB_CONTINUE;
 743
 744         /* FIXME: used to happen for instance during abandon
 745          * when global overlays are used... */
 746         assert( op->o_bd != NULL );
 747
 748         oi = op->o_bd->bd_info->bi_private;
 749         on = oi->oi_list;
 750
 751         if ( !SLAP_ISOVERLAY( op->o_bd )) {
 752                 db = *op->o_bd;
 753                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 754                 op->o_bd = &db;
 755         }
 756         cb->sc_cleanup = over_op_func_cleanup;
 757         cb->sc_response = over_back_response;
 758         cb->sc_writewait = NULL;
 759         cb->sc_next = op->o_callback;
 760         cb->sc_private = oi;
 761         op->o_callback = cb;
 762
 763         rc = overlay_op_walk( op, rs, which, oi, on );
 764         for ( sc = &op->o_callback; *sc; sc = &(*sc)->sc_next ) {
 765                 if ( *sc == cb ) {
 766                         *sc = cb->sc_next;
 767                         ch_free( cb );
 768                         break;
 769                 }
 770         }
 771
 772         op->o_bd = be;
 773         return rc;
 774 }
 775
 776 static int
 777 over_op_bind( Operation *op, SlapReply *rs )
 778 {
 779         return over_op_func( op, rs, op_bind );
 780 }
 781
 782 static int
 783 over_op_unbind( Operation *op, SlapReply *rs )
 784 {
 785         return over_op_func( op, rs, op_unbind );
 786 }
 787
 788 static int
 789 over_op_search( Operation *op, SlapReply *rs )
 790 {
 791         return over_op_func( op, rs, op_search );
 792 }
 793
 794 static int
 795 over_op_compare( Operation *op, SlapReply *rs )
 796 {
 797         return over_op_func( op, rs, op_compare );
 798 }
 799
 800 static int
 801 over_op_modify( Operation *op, SlapReply *rs )
 802 {
 803         return over_op_func( op, rs, op_modify );
 804 }
 805
 806 static int
 807 over_op_modrdn( Operation *op, SlapReply *rs )
 808 {
 809         return over_op_func( op, rs, op_modrdn );
 810 }
 811
 812 static int
 813 over_op_add( Operation *op, SlapReply *rs )
 814 {
 815         return over_op_func( op, rs, op_add );
 816 }
 817
 818 static int
 819 over_op_delete( Operation *op, SlapReply *rs )
 820 {
 821         return over_op_func( op, rs, op_delete );
 822 }
 823
 824 static int
 825 over_op_abandon( Operation *op, SlapReply *rs )
 826 {
 827         return over_op_func( op, rs, op_abandon );
 828 }
 829
 830 static int
 831 over_op_cancel( Operation *op, SlapReply *rs )
 832 {
 833         return over_op_func( op, rs, op_cancel );
 834 }
 835
 836 static int
 837 over_op_extended( Operation *op, SlapReply *rs )
 838 {
 839         return over_op_func( op, rs, op_extended );
 840 }
 841
 842 static int
 843 over_aux_operational( Operation *op, SlapReply *rs )
 844 {
 845         return over_op_func( op, rs, op_aux_operational );
 846 }
 847
 848 static int
 849 over_aux_chk_referrals( Operation *op, SlapReply *rs )
 850 {
 851         return over_op_func( op, rs, op_aux_chk_referrals );
 852 }
 853
 854 static int
 855 over_aux_chk_controls( Operation *op, SlapReply *rs )
 856 {
 857         return over_op_func( op, rs, op_aux_chk_controls );
 858 }
 859
 860 enum conn_which {
 861         conn_init = 0,
 862         conn_destroy,
 863         conn_last
 864 };
 865
 866 static int
 867 over_connection_func(
 868         BackendDB       *bd,
 869         Connection      *conn,
 870         enum conn_which which
 871 )
 872 {
 873         slap_overinfo           *oi;
 874         slap_overinst           *on;
 875         BackendDB               db;
 876         int                     rc = SLAP_CB_CONTINUE;
 877         BI_connection_init      **func;
 878
 879         /* FIXME: used to happen for instance during abandon
 880          * when global overlays are used... */
 881         assert( bd != NULL );
 882
 883         oi = bd->bd_info->bi_private;
 884         on = oi->oi_list;
 885
 886         if ( !SLAP_ISOVERLAY( bd ) ) {
 887                 db = *bd;
 888                 db.be_flags |= SLAP_DBFLAG_OVERLAY;
 889                 bd = &db;
 890         }
 891
 892         for ( ; on; on = on->on_next ) {
 893                 if ( on->on_bi.bi_flags & SLAPO_BFLAG_DISABLED )
 894                         continue;
 895                 func = &on->on_bi.bi_connection_init;
 896                 if ( func[ which ] ) {
 897                         bd->bd_info = (BackendInfo *)on;
 898                         rc = func[ which ]( bd, conn );
 899                         if ( rc != SLAP_CB_CONTINUE ) break;
 900                 }
 901         }
 902
 903         func = &oi->oi_orig->bi_connection_init;
 904         if ( func[ which ] && rc == SLAP_CB_CONTINUE ) {
 905                 bd->bd_info = oi->oi_orig;
 906                 rc = func[ which ]( bd, conn );
 907         }
 908         /* should not fall thru this far without anything happening... */
 909         if ( rc == SLAP_CB_CONTINUE ) {
 910                 rc = LDAP_UNWILLING_TO_PERFORM;
 911         }
 912
 913         return rc;
 914 }
 915
 916 static int
 917 over_connection_init(
 918         BackendDB       *bd,
 919         Connection      *conn
 920 )
 921 {
 922         return over_connection_func( bd, conn, conn_init );
 923 }
 924
 925 static int
 926 over_connection_destroy(
 927         BackendDB       *bd,
 928         Connection      *conn
 929 )
 930 {
 931         return over_connection_func( bd, conn, conn_destroy );
 932 }
 933
 934 int
 935 overlay_register(
 936         slap_overinst *on
 937 )
 938 {
 939         slap_overinst   *tmp;
 940
 941         /* FIXME: check for duplicates? */
 942         for ( tmp = overlays; tmp != NULL; tmp = tmp->on_next ) {
 943                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_type ) == 0 ) {
 944                         Debug( LDAP_DEBUG_ANY,
 945                                 "overlay_register(\"%s\"): "
 946                                 "name already in use.\n",
 947                                 on->on_bi.bi_type, 0, 0 );
 948                         return -1;
 949                 }
 950
 951                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 952                         int     i;
 953
 954                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 955                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], tmp->on_bi.bi_type ) == 0 ) {
 956                                         Debug( LDAP_DEBUG_ANY,
 957                                                 "overlay_register(\"%s\"): "
 958                                                 "obsolete name \"%s\" already in use "
 959                                                 "by overlay \"%s\".\n",
 960                                                 on->on_bi.bi_type,
 961                                                 on->on_bi.bi_obsolete_names[ i ],
 962                                                 tmp->on_bi.bi_type );
 963                                         return -1;
 964                                 }
 965                         }
 966                 }
 967
 968                 if ( tmp->on_bi.bi_obsolete_names != NULL ) {
 969                         int     i;
 970
 971                         for ( i = 0; tmp->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
 972                                 int     j;
 973
 974                                 if ( strcmp( on->on_bi.bi_type, tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 975                                         Debug( LDAP_DEBUG_ANY,
 976                                                 "overlay_register(\"%s\"): "
 977                                                 "name already in use "
 978                                                 "as obsolete by overlay \"%s\".\n",
 979                                                 on->on_bi.bi_type,
 980                                                 tmp->on_bi.bi_obsolete_names[ i ], 0 );
 981                                         return -1;
 982                                 }
 983
 984                                 if ( on->on_bi.bi_obsolete_names != NULL ) {
 985                                         for ( j = 0; on->on_bi.bi_obsolete_names[ j ] != NULL; j++ ) {
 986                                                 if ( strcmp( on->on_bi.bi_obsolete_names[ j ], tmp->on_bi.bi_obsolete_names[ i ] ) == 0 ) {
 987                                                         Debug( LDAP_DEBUG_ANY,
 988                                                                 "overlay_register(\"%s\"): "
 989                                                                 "obsolete name \"%s\" already in use "
 990                                                                 "as obsolete by overlay \"%s\".\n",
 991                                                                 on->on_bi.bi_type,
 992                                                                 on->on_bi.bi_obsolete_names[ j ],
 993                                                                 tmp->on_bi.bi_type );
 994                                                         return -1;
 995                                                 }
 996                                         }
 997                                 }
 998                         }
 999                 }
1000         }
1001
1002         on->on_next = overlays;
1003         overlays = on;
1004         return 0;
1005 }
1006
1007 /*
1008  * iterator on registered overlays; overlay_next( NULL ) returns the first
1009  * overlay; subsequent calls with the previously returned value allow to
1010  * iterate over the entire list; returns NULL when no more overlays are
1011  * registered.
1012  */
1013
1014 slap_overinst *
1015 overlay_next(
1016         slap_overinst *on
1017 )
1018 {
1019         if ( on == NULL ) {
1020                 return overlays;
1021         }
1022
1023         return on->on_next;
1024 }
1025
1026 /*
1027  * returns a specific registered overlay based on the type; NULL if not
1028  * registered.
1029  */
1030
1031 slap_overinst *
1032 overlay_find( const char *over_type )
1033 {
1034         slap_overinst *on = overlays;
1035
1036         assert( over_type != NULL );
1037
1038         for ( ; on; on = on->on_next ) {
1039                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1040                         goto foundit;
1041                 }
1042
1043                 if ( on->on_bi.bi_obsolete_names != NULL ) {
1044                         int     i;
1045
1046                         for ( i = 0; on->on_bi.bi_obsolete_names[ i ] != NULL; i++ ) {
1047                                 if ( strcmp( on->on_bi.bi_obsolete_names[ i ], over_type ) == 0 ) {
1048                                         Debug( LDAP_DEBUG_ANY,
1049                                                 "overlay_find(\"%s\"): "
1050                                                 "obsolete name for \"%s\".\n",
1051                                                 on->on_bi.bi_obsolete_names[ i ],
1052                                                 on->on_bi.bi_type, 0 );
1053                                         goto foundit;
1054                                 }
1055                         }
1056                 }
1057         }
1058
1059 foundit:;
1060         return on;
1061 }
1062
1063 static const char overtype[] = "over";
1064
1065 /*
1066  * returns TRUE (1) if the database is actually an overlay instance;
1067  * FALSE (0) otherwise.
1068  */
1069
1070 int
1071 overlay_is_over( BackendDB *be )
1072 {
1073         return be->bd_info->bi_type == overtype;
1074 }
1075
1076 /*
1077  * returns TRUE (1) if the given database is actually an overlay
1078  * instance and, somewhere in the list, contains the requested overlay;
1079  * FALSE (0) otherwise.
1080  */
1081
1082 int
1083 overlay_is_inst( BackendDB *be, const char *over_type )
1084 {
1085         slap_overinst   *on;
1086
1087         assert( be != NULL );
1088
1089         if ( !overlay_is_over( be ) ) {
1090                 return 0;
1091         }
1092
1093         on = ((slap_overinfo *)be->bd_info->bi_private)->oi_list;
1094         for ( ; on; on = on->on_next ) {
1095                 if ( strcmp( on->on_bi.bi_type, over_type ) == 0 ) {
1096                         return 1;
1097                 }
1098         }
1099
1100         return 0;
1101 }
1102
1103 int
1104 overlay_register_control( BackendDB *be, const char *oid )
1105 {
1106         int             gotit = 0;
1107         int             cid;
1108
1109         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1110                 return -1;
1111         }
1112
1113         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1114                 BackendDB *bd;
1115
1116                 /* add to all backends... */
1117                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1118                         if ( bd == be->bd_self ) {
1119                                 gotit = 1;
1120                         }
1121
1122                         /* overlays can be instanciated multiple times, use
1123                          * be_ctrls[ cid ] as an instance counter, so that the
1124                          * overlay's controls are only really disabled after the
1125                          * last instance called overlay_register_control() */
1126                         bd->be_ctrls[ cid ]++;
1127                         bd->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1128                 }
1129
1130         }
1131
1132         if ( !gotit ) {
1133                 /* overlays can be instanciated multiple times, use
1134                  * be_ctrls[ cid ] as an instance counter, so that the
1135                  * overlay's controls are only really unregistered after the
1136                  * last instance called overlay_register_control() */
1137                 be->bd_self->be_ctrls[ cid ]++;
1138                 be->bd_self->be_ctrls[ SLAP_MAX_CIDS ] = 1;
1139         }
1140
1141         return 0;
1142 }
1143
1144 #ifdef SLAP_CONFIG_DELETE
1145 void
1146 overlay_unregister_control( BackendDB *be, const char *oid )
1147 {
1148         int             gotit = 0;
1149         int             cid;
1150
1151         if ( slap_find_control_id( oid, &cid ) == LDAP_CONTROL_NOT_FOUND ) {
1152                 return;
1153         }
1154
1155         if ( SLAP_ISGLOBALOVERLAY( be ) ) {
1156                 BackendDB *bd;
1157
1158                 /* remove from all backends... */
1159                 LDAP_STAILQ_FOREACH( bd, &backendDB, be_next ) {
1160                         if ( bd == be->bd_self ) {
1161                                 gotit = 1;
1162                         }
1163
1164                         bd->be_ctrls[ cid ]--;
1165                 }
1166         }
1167
1168         if ( !gotit ) {
1169                 be->bd_self->be_ctrls[ cid ]--;
1170         }
1171 }
1172 #endif /* SLAP_CONFIG_DELETE */
1173
1174 void
1175 overlay_destroy_one( BackendDB *be, slap_overinst *on )
1176 {
1177         slap_overinfo *oi = on->on_info;
1178         slap_overinst **oidx;
1179
1180         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1181                 if ( *oidx == on ) {
1182                         *oidx = on->on_next;
1183                         if ( on->on_bi.bi_db_destroy ) {
1184                                 BackendInfo *bi_orig = be->bd_info;
1185                                 be->bd_info = (BackendInfo *)on;
1186                                 on->on_bi.bi_db_destroy( be, NULL );
1187                                 be->bd_info = bi_orig;
1188                         }
1189                         free( on );
1190                         break;
1191                 }
1192         }
1193 }
1194
1195 #ifdef SLAP_CONFIG_DELETE
1196 typedef struct ov_remove_ctx {
1197         BackendDB *be;
1198         slap_overinst *on;
1199 } ov_remove_ctx;
1200
1201 int
1202 overlay_remove_cb( Operation *op, SlapReply *rs )
1203 {
1204         ov_remove_ctx *rm_ctx = (ov_remove_ctx*) op->o_callback->sc_private;
1205         BackendInfo *bi_orig = rm_ctx->be->bd_info;
1206
1207         rm_ctx->be->bd_info = (BackendInfo*) rm_ctx->on;
1208
1209         if ( rm_ctx->on->on_bi.bi_db_close ) {
1210                 rm_ctx->on->on_bi.bi_db_close( rm_ctx->be, NULL );
1211         }
1212         if ( rm_ctx->on->on_bi.bi_db_destroy ) {
1213                 rm_ctx->on->on_bi.bi_db_destroy( rm_ctx->be, NULL );
1214         }
1215
1216         /* clean up after removing last overlay */
1217         if ( ! rm_ctx->on->on_info->oi_list ) {
1218                 /* reset db flags and bd_info to orig */
1219                 SLAP_DBFLAGS( rm_ctx->be ) &= ~SLAP_DBFLAG_GLOBAL_OVERLAY;
1220                 rm_ctx->be->bd_info = rm_ctx->on->on_info->oi_orig;
1221                 ch_free(rm_ctx->on->on_info);
1222         } else {
1223                 rm_ctx->be->bd_info = bi_orig;
1224         }
1225         free( rm_ctx->on );
1226         op->o_tmpfree(rm_ctx, op->o_tmpmemctx);
1227         return SLAP_CB_CONTINUE;
1228 }
1229
1230 void
1231 overlay_remove( BackendDB *be, slap_overinst *on, Operation *op )
1232 {
1233         slap_overinfo *oi = on->on_info;
1234         slap_overinst **oidx;
1235         ov_remove_ctx *rm_ctx;
1236         slap_callback *rm_cb, *cb;
1237
1238         /* remove overlay from oi_list */
1239         for ( oidx = &oi->oi_list; *oidx; oidx = &(*oidx)->on_next ) {
1240                 if ( *oidx == on ) {
1241                         *oidx = on->on_next;
1242                         break;
1243                 }
1244         }
1245
1246         /* The db_close and db_destroy handlers to cleanup a release
1247          * the overlay's resources are called from the cleanup callback
1248          */
1249         rm_ctx = op->o_tmpalloc( sizeof( ov_remove_ctx ), op->o_tmpmemctx );
1250         rm_ctx->be = be;
1251         rm_ctx->on = on;
1252
1253         rm_cb = op->o_tmpalloc( sizeof( slap_callback ), op->o_tmpmemctx );
1254         rm_cb->sc_next = NULL;
1255         rm_cb->sc_cleanup = overlay_remove_cb;
1256         rm_cb->sc_response = NULL;
1257         rm_cb->sc_private = (void*) rm_ctx;
1258         rm_cb->sc_writewait = NULL;
1259
1260         /* Append callback to the end of the list */
1261         if ( !op->o_callback ) {
1262                 op->o_callback = rm_cb;
1263         } else {
1264                 for ( cb = op->o_callback; cb->sc_next; cb = cb->sc_next );
1265                 cb->sc_next = rm_cb;
1266         }
1267 }
1268 #endif /* SLAP_CONFIG_DELETE */
1269
1270 void
1271 overlay_insert( BackendDB *be, slap_overinst *on2, slap_overinst ***prev,
1272         int idx )
1273 {
1274         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1275
1276         if ( idx == -1 ) {
1277                 on2->on_next = oi->oi_list;
1278                 oi->oi_list = on2;
1279         } else {
1280                 int i, novs;
1281                 slap_overinst *on, **prev;
1282
1283                 /* Since the list is in reverse order and is singly linked,
1284                  * we have to count the overlays and then insert backwards.
1285                  * Adding on overlay at a specific point should be a pretty
1286                  * infrequent occurrence.
1287                  */
1288                 novs = 0;
1289                 for ( on = oi->oi_list; on; on=on->on_next )
1290                         novs++;
1291
1292                 if (idx > novs)
1293                         idx = 0;
1294                 else
1295                         idx = novs - idx;
1296
1297                 /* advance to insertion point */
1298                 prev = &oi->oi_list;
1299                 for ( i=0; i<idx; i++ ) {
1300                         on = *prev;
1301                         prev = &on->on_next;
1302                 }
1303                 /* insert */
1304                 on2->on_next = *prev;
1305                 *prev = on2;
1306         }
1307 }
1308
1309 void
1310 overlay_move( BackendDB *be, slap_overinst *on, int idx )
1311 {
1312         slap_overinfo *oi = (slap_overinfo *)be->bd_info;
1313         slap_overinst **onp;
1314
1315         for (onp = &oi->oi_list; *onp; onp= &(*onp)->on_next) {
1316                 if ( *onp == on ) {
1317                         *onp = on->on_next;
1318                         break;
1319                 }
1320         }
1321         overlay_insert( be, on, &onp, idx );
1322 }
1323
1324 /* add an overlay to a particular backend. */
1325 int
1326 overlay_config( BackendDB *be, const char *ov, int idx, BackendInfo **res, ConfigReply *cr )
1327 {
1328         slap_overinst *on = NULL, *on2 = NULL, **prev;
1329         slap_overinfo *oi = NULL;
1330         BackendInfo *bi = NULL;
1331
1332         if ( res )
1333                 *res = NULL;
1334
1335         on = overlay_find( ov );
1336         if ( !on ) {
1337                 Debug( LDAP_DEBUG_ANY, "overlay \"%s\" not found\n", ov, 0, 0 );
1338                 return 1;
1339         }
1340
1341         /* If this is the first overlay on this backend, set up the
1342          * overlay info structure
1343          */
1344         if ( !overlay_is_over( be ) ) {
1345                 int     isglobal = 0;
1346
1347                 /* NOTE: the first time a global overlay is configured,
1348                  * frontendDB gets this flag; it is used later by overlays
1349                  * to determine if they're stacked on top of the frontendDB */
1350                 if ( be->bd_info == frontendDB->bd_info || SLAP_ISGLOBALOVERLAY( be ) ) {
1351                         isglobal = 1;
1352                         if ( on->on_bi.bi_flags & SLAPO_BFLAG_DBONLY ) {
1353                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1354                                         "overlay \"%s\" cannot be global.\n",
1355                                         ov, 0, 0 );
1356                                 return 1;
1357                         }
1358
1359                 } else if ( on->on_bi.bi_flags & SLAPO_BFLAG_GLOBONLY ) {
1360                         Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1361                                 "overlay \"%s\" can only be global.\n",
1362                                 ov, 0, 0 );
1363                         return 1;
1364                 }
1365
1366                 oi = ch_malloc( sizeof( slap_overinfo ) );
1367                 oi->oi_orig = be->bd_info;
1368                 oi->oi_bi = *be->bd_info;
1369                 oi->oi_origdb = be;
1370
1371                 if ( isglobal ) {
1372                         SLAP_DBFLAGS( be ) |= SLAP_DBFLAG_GLOBAL_OVERLAY;
1373                 }
1374
1375                 /* Save a pointer to ourself in bi_private.
1376                  */
1377                 oi->oi_bi.bi_private = oi;
1378                 oi->oi_list = NULL;
1379                 bi = (BackendInfo *)oi;
1380
1381                 bi->bi_type = (char *)overtype;
1382
1383                 bi->bi_db_config = over_db_config;
1384                 bi->bi_db_open = over_db_open;
1385                 bi->bi_db_close = over_db_close;
1386                 bi->bi_db_destroy = over_db_destroy;
1387
1388                 bi->bi_op_bind = over_op_bind;
1389                 bi->bi_op_unbind = over_op_unbind;
1390                 bi->bi_op_search = over_op_search;
1391                 bi->bi_op_compare = over_op_compare;
1392                 bi->bi_op_modify = over_op_modify;
1393                 bi->bi_op_modrdn = over_op_modrdn;
1394                 bi->bi_op_add = over_op_add;
1395                 bi->bi_op_delete = over_op_delete;
1396                 bi->bi_op_abandon = over_op_abandon;
1397                 bi->bi_op_cancel = over_op_cancel;
1398
1399                 bi->bi_extended = over_op_extended;
1400
1401                 /*
1402                  * this is fine because it has the same
1403                  * args of the operations; we need to rework
1404                  * all the hooks to share the same args
1405                  * of the operations...
1406                  */
1407                 bi->bi_operational = over_aux_operational;
1408                 bi->bi_chk_referrals = over_aux_chk_referrals;
1409                 bi->bi_chk_controls = over_aux_chk_controls;
1410
1411                 /* these have specific arglists */
1412                 bi->bi_entry_get_rw = over_entry_get_rw;
1413                 bi->bi_entry_release_rw = over_entry_release_rw;
1414                 bi->bi_access_allowed = over_access_allowed;
1415                 bi->bi_acl_group = over_acl_group;
1416                 bi->bi_acl_attribute = over_acl_attribute;
1417
1418                 bi->bi_connection_init = over_connection_init;
1419                 bi->bi_connection_destroy = over_connection_destroy;
1420
1421                 be->bd_info = bi;
1422
1423         } else {
1424                 if ( overlay_is_inst( be, ov ) ) {
1425                         if ( SLAPO_SINGLE( be ) ) {
1426                                 Debug( LDAP_DEBUG_ANY, "overlay_config(): "
1427                                         "overlay \"%s\" already in list\n",
1428                                         ov, 0, 0 );
1429                                 return 1;
1430                         }
1431                 }
1432
1433                 oi = be->bd_info->bi_private;
1434         }
1435
1436         /* Insert new overlay into list. By default overlays are
1437          * added to head of list and executed in LIFO order.
1438          */
1439         on2 = ch_calloc( 1, sizeof(slap_overinst) );
1440         *on2 = *on;
1441         on2->on_info = oi;
1442
1443         prev = &oi->oi_list;
1444         /* Do we need to find the insertion point? */
1445         if ( idx >= 0 ) {
1446                 int i;
1447
1448                 /* count current overlays */
1449                 for ( i=0, on=oi->oi_list; on; on=on->on_next, i++ );
1450
1451                 /* are we just appending a new one? */
1452                 if ( idx >= i )
1453                         idx = -1;
1454         }
1455         overlay_insert( be, on2, &prev, idx );
1456
1457         /* Any initialization needed? */
1458         if ( on2->on_bi.bi_db_init ) {
1459                 int rc;
1460                 be->bd_info = (BackendInfo *)on2;
1461                 rc = on2->on_bi.bi_db_init( be, cr);
1462                 be->bd_info = (BackendInfo *)oi;
1463                 if ( rc ) {
1464                         *prev = on2->on_next;
1465                         ch_free( on2 );
1466                         on2 = NULL;
1467                         return rc;
1468                 }
1469         }
1470
1471         if ( res )
1472                 *res = &on2->on_bi;
1473
1474         return 0;
1475 }